Microwave frequency switching delays in phase-locked period-one dynamics of semiconductor lasers.

Modern microwave switches require high switching speeds to rapidly route data over multiple radio channels while minimizing the routing delay. This Letter proposes a novel, to the best of our knowledge, microwave frequency switching system using phase-locked Period-one (P1) dynamics of semiconductor lasers. When a semiconductor laser is optically injected by microwave-modulated optical signals, which carry two-tone input microwaves at 29 and 37 GHz, with proper injection power controlled by dual-voltage control signals, P1 dynamics are excited in the semiconductor laser and subsequently phase-locked by one of the input microwave tones. We have observed positive and negative switching delays in the switching process. For instance, a positive delay is observed when the system requires additional optical power to transition from a phase-locked state at 29 GHz to an unlocked state. Conversely, a negative delay occurs when the unlocked P1 dynamics approach but do not reach a 37-GHz frequency and then rapidly lock to the tone, thereby surpassing the speed of the control signals. These dual delays are instrumental in enhancing the switching speed of our system, enabling it to surpass the voltage switching time of the control signals by a factor of 3.6. In addition, by leveraging these dual delays, the duration of the microwave tones can be further extended in the switching process.

Absence of Slc39a14/Zip14 in mouse pancreatic beta cells results in hyperinsulinemia.

Zinc is an essential component of the insulin protein complex synthesized in ß cells. The intracellular compartmentalization and distribution of zinc are controlled by 24 transmembrane zinc transporters belonging to the ZnT or Zrt/Irt-like protein (ZIP) family. Downregulation of SLC39A14/ZIP14 has been reported in pancreatic islets of patients with type 2 diabetes (T2D) as well as mouse models of high-fat diet (HFD)- or db/db-induced obesity. Our previous studies observed mild hyperinsulinemia in mice with whole body knockout of Slc39a14 (Zip14 KO). Based on our current secondary data analysis from an integrative single-cell RNA-seq dataset of human whole pancreatic tissue, SLC39A14 (coding ZIP14) is the only other zinc transporter expressed abundantly in human ß cells besides well-known zinc transporter SLC30A8 (coding ZnT8). In the present work, using pancreatic ß cell-specific knockout of Slc39a14 (ß-Zip14 KO), we investigated the role of SLC39A14/ZIP14-mediated intracellular zinc trafficking in glucose-stimulated insulin secretion and subsequent metabolic responses. Glucose-stimulated insulin secretion, zinc concentrations, and cellular localization of ZIP14 were assessed using in vivo, ex vivo, and in vitro assays using ß-Zip14 KO, isolated islets, and murine cell line MIN6. Metabolic evaluations were done on both chow- and HFD-fed mice using time-domain nuclear magnetic resonance and a comprehensive laboratory animal monitoring system. ZIP14 localizes on the endoplasmic reticulum regulating intracellular zinc trafficking in ß cells and serves as a negative regulator of glucose-stimulated insulin secretion. Deletion of Zip14 resulted in greater glucose-stimulated insulin secretion, increased energy expenditure, and shifted energy metabolism toward fatty acid utilization. HFD caused ß-Zip14 KO mice to develop greater islet hyperplasia, compensatory hyperinsulinemia, and mild insulin resistance and hyperglycemia. This study provided new insights into the contribution of metal transporter ZIP14-mediated intracellular zinc trafficking in glucose-stimulated insulin secretion and subsequent metabolic responses.NEW & NOTEWORTHY Metal transporter SLC39A14/ZIP14 is downregulated in pancreatic islets of patients with T2D and mouse models of HFD- or db/db-induced obesity. However, the function of ZIP14-mediated intracellular zinc trafficking in ß cells is unknown. Our analyses revealed that SLC39A14 is the only Zn transporter expressed abundantly in human ß cells besides SLC30A8. Within the ß cells, ZIP14 is localized on the endoplasmic reticulum and serves as a negative regulator of insulin secretion, providing a potential therapeutic target for T2D.

Optical frequency comb generation using cascaded injection of semiconductor lasers.

We study optical frequency comb (OFC) generation using cascaded injection of semiconductor lasers in this work. The OFC generation system is operated in two cascaded optical injection stages. When a master laser optically injects into the first stage with proper injection power and frequency, period-one (P1) dynamics are invoked in an optically injected semiconductor laser of the first stage. Another semiconductor laser in the second stage is then optically injected by the P1 dynamics. With proper injection power adjusted in the second stage, the P1 dynamics are regenerated, and the semiconductor laser relaxation oscillations (ROs) become undamped so that subharmonic oscillations appear. Because a subharmonic oscillation frequency is half of an oscillation frequency of the P1 dynamics, extra optical frequency components appear in the middle of the adjacent optical frequency components of the P1 dynamics, thus signaling OFC generation. The OFC signals exhibit at least 15 comb lines, resulting in a bandwidth greater than 140 GHz. Microwave comb signals are obtained after photodetection, although the microwave linewidth is on the order of a few megahertz because of the semiconductor laser noise. Thus, we propose a cascaded injection-locking scheme to stabilize the P1 dynamics and OFC signals. We have demonstrated pure microwave generations with a linewidth of less than 3 Hz and low phase noise.

Integrative genome-scale analyses reveal post-transcriptional signatures of early human small intestinal development in a directed differentiation organoid model.

BACKGROUND: MicroRNAs (miRNAs) are important post-transcriptional gene regulators controlling cellular lineage specification and differentiation during embryonic development, including the gastrointestinal system. However, miRNA-mediated regulatory mechanisms involved in early embryonic development of human small intestine (SI) remains underexplored. To explore candidate roles for miRNAs in prenatal SI lineage specification in humans, we used a multi-omic analysis strategy in a directed differentiation model that programs human pluripotent stem cells toward the SI lineage. RESULTS: We leveraged small RNA-seq to define the changing miRNA landscape, and integrated chromatin run-on sequencing (ChRO-seq) and RNA-seq to define genes subject to significant post-transcriptional regulation across the different stages of differentiation. Small RNA-seq profiling revealed temporal dynamics of miRNA signatures across different developmental events of the model, including definitive endoderm formation, SI lineage specification and SI regional patterning. Our multi-omic, integrative analyses showed further that the elevation of miR-182 and reduction of miR-375 are key events during SI lineage specification. We demonstrated that loss of miR-182 leads to an increase in the foregut master marker SOX2. We also used single-cell analyses in murine adult intestinal crypts to support a life-long role for miR-375 in the regulation of Zfp36l2. Finally, we uncovered opposing roles of SMAD4 and WNT signaling in regulating miR-375 expression during SI lineage specification. Beyond the mechanisms highlighted in this study, we also present a web-based application for exploration of post-transcriptional regulation and miRNA-mediated control in the context of early human SI development. CONCLUSION: The present study uncovers a novel facet of miRNAs in regulating prenatal SI development. We leveraged multi-omic, systems biology approaches to discover candidate miRNA regulators associated with early SI developmental events in a human organoid model. In this study, we highlighted miRNA-mediated post-transcriptional regulation relevant to the event of SI lineage specification. The candidate miRNA regulators that we identified for the other stages of SI development also warrant detailed characterization in the future.

Sucrose-induced hyperglycemia dysregulates intestinal zinc metabolism and integrity: risk factors for chronic diseases.

Objective: Zinc is an essential micronutrient that is critical for many physiological processes, including glucose metabolism, regulation of inflammation, and intestinal barrier function. Further, zinc dysregulation is associated with an increased risk of chronic inflammatory diseases such as type II diabetes, obesity, and inflammatory bowel disease. However, whether altered zinc status is a symptom or cause of disease onset remains unclear. Common symptoms of these three chronic diseases include the onset of increased intestinal permeability and zinc dyshomeostasis. The specific focus of this work is to investigate how dietary sources of intestinal permeability, such as high sucrose consumption, impact transporter-mediated zinc homeostasis and subsequent zinc-dependent physiology contributing to disease development. Method: We used in vivo subchronic sucrose treatment, ex vivo intestinal organoid culture, and in vitro cell systems. We analyze the alterations in zinc metabolism and intestinal permeability and metabolic outcomes. Results: We found that subchronic sucrose treatment resulted in systemic changes in steady-state zinc distribution and increased 65Zn transport (blood-to-intestine) along with greater ZIP14 expression at the basolateral membrane of the intestine. Further, sucrose treatment enhanced cell survival of intestinal epithelial cells, activation of the EGFR-AKT-STAT3 pathway, and intestinal permeability. Conclusion: Our work suggests that subchronic high sucrose consumption alters systemic and intestinal zinc homeostasis linking diet-induced changes in zinc homeostasis to the intestinal permeability and onset of precursors for chronic disease.

Human pancreatic islet microRNAs implicated in diabetes and related traits by large-scale genetic analysis.

Genetic studies have identified ≥240 loci associated with the risk of type 2 diabetes (T2D), yet most of these loci lie in non-coding regions, masking the underlying molecular mechanisms. Recent studies investigating mRNA expression in human pancreatic islets have yielded important insights into the molecular drivers of normal islet function and T2D pathophysiology. However, similar studies investigating microRNA (miRNA) expression remain limited. Here, we present data from 63 individuals, the largest sequencing-based analysis of miRNA expression in human islets to date. We characterized the genetic regulation of miRNA expression by decomposing the expression of highly heritable miRNAs into cis- and trans-acting genetic components and mapping cis-acting loci associated with miRNA expression [miRNA-expression quantitative trait loci (eQTLs)]. We found i) 84 heritable miRNAs, primarily regulated by trans-acting genetic effects, and ii) 5 miRNA-eQTLs. We also used several different strategies to identify T2D-associated miRNAs. First, we colocalized miRNA-eQTLs with genetic loci associated with T2D and multiple glycemic traits, identifying one miRNA, miR-1908, that shares genetic signals for blood glucose and glycated hemoglobin (HbA1c). Next, we intersected miRNA seed regions and predicted target sites with credible set SNPs associated with T2D and glycemic traits and found 32 miRNAs that may have altered binding and function due to disrupted seed regions. Finally, we performed differential expression analysis and identified 14 miRNAs associated with T2D status-including miR-187-3p, miR-21-5p, miR-668, and miR-199b-5p-and 4 miRNAs associated with a polygenic score for HbA1c levels-miR-216a, miR-25, miR-30a-3p, and miR-30a-5p.

Chronic kidney disease promotes cerebral microhemorrhage formation.

BACKGROUND: Chronic kidney disease (CKD) is increasingly recognized as a stroke risk factor, but its exact relationship with cerebrovascular disease is not well-understood. We investigated the development of cerebral small vessel disease using in vivo and in vitro models of CKD. METHODS: CKD was produced in aged C57BL/6J mice using an adenine-induced tubulointerstitial nephritis model. We analyzed brain histology using Prussian blue staining to examine formation of cerebral microhemorrhage (CMH), the hemorrhagic component of small vessel disease and the neuropathological substrate of MRI-demonstrable cerebral microbleeds. In cell culture studies, we examined effects of serum from healthy or CKD patients and gut-derived uremic toxins on brain microvascular endothelial barrier. RESULTS: CKD was induced in aged C57BL/6J mice with significant increases in both serum creatinine and cystatin C levels (p < 0.0001) without elevation of systolic or diastolic blood pressure. CMH was significantly increased and positively correlated with serum creatinine level (Spearman r = 0.37, p < 0.01). Moreover, CKD significantly increased Iba-1-positive immunoreactivity by 51% (p < 0.001), induced a phenotypic switch from resting to activated microglia, and enhanced fibrinogen extravasation across the blood-brain barrier (BBB) by 34% (p < 0.05). On analysis stratified by sex, the increase in CMH number was more pronounced in male mice and this correlated with greater creatinine elevation in male compared with female mice. Microglial depletion with PLX3397 diet significantly decreased CMH formation in CKD mice without affecting serum creatinine levels. Incubation of CKD serum significantly reduced transendothelial electrical resistance (TEER) (p < 0.01) and increased sodium fluorescein permeability (p < 0.05) across the endothelial monolayer. Uremic toxins (i.e., indoxyl sulfate, p-cresyl sulfate, and trimethylamine-N-oxide) in combination with urea and lipopolysaccharide induced a marked drop in TEER compared with the control group (p < 0.0001). CONCLUSIONS: CKD promotes the development of CMH in aged mice independent of blood pressure but directly proportional to the degree of renal impairment. These effects of CKD are likely mediated in part by microglia and are associated with BBB impairment. The latter is likely related to gut-derived bacteria-dependent toxins classically associated with CKD. Overall, these findings demonstrate an important role of CKD in the development of cerebral small vessel disease.

Ultraclean and Facile Patterning of CVD Graphene by a UV-Light-Assisted Dry Transfer Method.

The synthesis of large-area graphene by the chemical vapor deposition (CVD) method is a mature technology; however, a transfer procedure is required to integrate CVD-grown graphene into a functional device. The reported methods for transferring graphene films cause different degrees of defects (cracking, rupture) and ion/polymer residues, which deteriorate or alter the electrical properties of as-grown graphene. Developing a reliable and fast transfer method that can maintain high-quality graphene remains a challenge. In this work, we employed UV light release tape (UV-RT) as the support layer to replace the frequently used thermal release tape (TRT) in a typical roll-to-roll dry transfer process. In this process, we used an easier-to-remove polymer as an adhesion layer to greatly reduce the strain and defects that occur during the transfer process. The cleanliness of graphene transferred by this method is above 99%, and the carrier mobility is 1.6 and 1.1 times higher than that obtained with conventional wet transfer and TRT transfer methods, respectively. UV illumination leads to facile and uniform release of the graphene film onto the target substrate, achieving one-step and selective patterning of graphene (feature size of <100 µm). The UV-assisted decomposition of the polymer molecular structure into small molecules enables a residue-free and ultraclean graphene surface. This proposed transfer method enables facile patterning of graphene and 2D films while maintaining high quality, which paves the way for versatile functional graphene applications.

Human duodenal submucosal glands contain a defined stem/progenitor subpopulation with liver-specific regenerative potential.

BACKGROUND & AIMS: Common precursors for the liver, biliary tree, and pancreas exist at an early stage of development in the definitive endoderm forming the foregut. We have identified and characterised endodermal stem/progenitor cells with regenerative potential persisting in the adult human duodenum. METHODS: Human duodena were obtained from organ donors, and duodenal submucosal gland cells were isolated after removal of the mucosa layer. Cells were cultured on plastic or as organoids and were transplanted into severe combined immunodeficient (SCID) mouse livers. RESULTS: In situ studies of submucosal glands in the human duodenum revealed cells expressing stem/progenitor cell markers that had unique phenotypic traits distinguishable from intestinal crypt cells. Genetic signature studies indicated that the cells are closer to biliary tree stem cells and to definitive endodermal cells than to adult hepatocytes, supporting the interpretation that they are endodermal stem/progenitor cells. In vitro, human duodenal submucosal gland cells demonstrated clonal growth, capability to form organoids, and ability to acquire functional hepatocyte traits. In vivo, transplanted cells engrafted into the livers of immunocompromised mice and differentiated to mature liver cells. In an experimental model of fatty liver, human duodenal submucosal gland cells were able to rescue hosts from liver damage by supporting repopulation and regeneration of the liver. CONCLUSIONS: A cell population with clonal growth and organoid formation capability, which has liver differentiation potency in vitro and in vivo in murine experimental models, is present within adult duodenal submucosal glands. These cells can be isolated, do not require reprogramming, and thus could potentially represent a novel cell source for regenerative medicine of the liver. IMPACT AND IMPLICATIONS: Cell therapies for liver disease could represent an option to support liver function, but the identification of sustainable and viable cell sources is critical. Here, we describe a cell population with organoid formation capability and liver-specific regenerative potential in submucosal glands of the human duodenum. Duodenal submucosal gland cells are isolated from adult organs, do not require reprogramming, and could rescue hepatocellular damage in preclinical models of chronic, but not acute, liver injury. Duodenal submucosal gland cells could represent a potential candidate cell source for regenerative medicine of the liver, but the determination of cell dose and toxicity is needed before clinical testing in humans.

Polyaniline Composites Containing Eco-Friendly Biomass Carbon from Agricultural-Waste Coconut Husk for Enhancing Gas Sensor Performance in Hydrogen Sulfide Detection.

Hydrogen sulfide, a colorless, flammable gas with a distinct rotten egg odor, poses severe health risks in industrial settings. Sensing hydrogen sulfide is crucial for safeguarding worker safety and preventing potential accidents. This study investigated the gas-sensing performance of an electroactive polymer (i.e., polyaniline, PANI) and its composites with active carbon (AC) (i.e., PANI-AC1 and PANI-AC3) toward H2S at room temperature. PANI-AC composites-coated IDE gas sensors were fabricated and their capability of detecting H2S at concentrations ranging from 1 ppm to 30 ppm was tested. The superior gas-sensing performance of the PANI-AC composites can be attributed to the increased surface area of the materials, which provided increased active sites for doping processes and enhanced the sensing capability of the composites. Specifically, the incorporation of AC in the PANI matrix resulted in a substantial improvement in the doping process, which led to stronger gas-sensing responses with higher repeatability and higher stability toward H2S compared to the neat PANI-coated IDE sensor. Furthermore, the as-prepared IDE gas sensor exhibited the best sensing response toward H2S at 60% RH. The use of agricultural-waste coconut husk for the synthesis of these high-performance gas-sensing materials promotes sustainable and eco-friendly practices while improving the detection and monitoring of H2S gas in industrial settings.

ECIS Based Electric Fence Method for Measurement of Human Keratinocyte Migration on Different Substrates.

Electric Cell-substrate Impedance Sensing (ECIS) is an impedance-based, real-time, and label-free measuring system for monitoring cellular activities in tissue culture. Previously, ECIS wound healing assay has been used to wound cells with high electric current and monitor the subsequent cell migration. In this study, we applied ECIS electric fence (EF) method, an alternative to electrical wounding, to assess the effects of different surface coatings on human keratinocyte (HaCaT) migration. The EF prevents inoculated cells from attaching or migrating to the fenced electrode surface while maintaining the integrity of the surface coating. After the EF is turned off, cells migrate into the cell-free area, and the increase in measured impedance is monitored. We cultured HaCaT cells on gold electrodes without coating or coated with poly-L-lysin (PLL), poly-D-lysine (PDL), or type-I collagen. We quantified migration rates according to the different slopes in the impedance time series. It was observed that either poly-L-lysine (PLL) or poly-D-lysine (PDL) limits cell adhesion and migration rates. Furthermore, the surface charge of the coated substrate in the culture condition positively correlates with the cell adhesion and migration process. Our results indicate that the EF method is useful for determining cell migration rates on specific surface coatings.

Vertical sleeve gastrectomy induces enteroendocrine cell differentiation of intestinal stem cells through bile acid signaling.

Vertical sleeve gastrectomy (VSG) results in an increase in the number of hormone-secreting enteroendocrine cells (EECs) in the intestinal epithelium; however, the mechanism remains unclear. Notably, the beneficial effects of VSG are lost in a mouse model lacking the nuclear bile acid receptor farnesoid X receptor (FXR). FXR is a nuclear transcription factor that has been shown to regulate intestinal stem cell (ISC) function in cancer models. Therefore, we hypothesized that the VSG-induced increase in EECs is due to changes in intestinal differentiation driven by an increase in bile acid signaling through FXR. To test this, we performed VSG in mice that express EGFP in ISC/progenitor cells and performed RNA-Seq on GFP-positive cells sorted from the intestinal epithelia. We also assessed changes in EEC number (marked by glucagon-like peptide-1, GLP-1) in mouse intestinal organoids following treatment with bile acids, an FXR agonist, and an FXR antagonist. RNA-Seq of ISCs revealed that bile acid receptors are expressed in ISCs and that VSG explicitly alters expression of several genes that regulate EEC differentiation. Mouse intestinal organoids treated with bile acids and 2 different FXR agonists increased GLP-1-positive cell numbers, and administration of an FXR antagonist blocked these effects. Taken together, these data indicate that VSG drives ISC fate toward EEC differentiation through bile acid signaling.

Candidate master microRNA regulator of arsenic-induced pancreatic beta cell impairment revealed by multi-omics analysis.

Arsenic is a pervasive environmental toxin that is listed as the top priority for investigation by the Agency for Toxic Substance and Disease Registry. While chronic exposure to arsenic is associated with type 2 diabetes (T2D), the underlying mechanisms are largely unknown. We have recently demonstrated that arsenic treatment of INS-1 832/13 pancreatic beta cells impairs glucose-stimulated insulin secretion (GSIS), a T2D hallmark. We have also shown that arsenic alters the microRNA profile of beta cells. MicroRNAs have a well-established post-transcriptional regulatory role in both normal beta cell function and T2D pathogenesis. We hypothesized that there are microRNA master regulators that shape beta cell gene expression in pathways pertinent to GSIS after exposure to arsenicals. To test this hypothesis, we first treated INS-1 832/13 beta cells with either inorganic arsenic (iAsIII) or monomethylarsenite (MAsIII) and confirmed GSIS impairment. We then performed multi-omic analysis using chromatin run-on sequencing, RNA-sequencing, and small RNA-sequencing to define profiles of transcription, gene expression, and microRNAs, respectively. Integrating across these data sets, we first showed that genes downregulated by iAsIII treatment are enriched in insulin secretion and T2D pathways, whereas genes downregulated by MAsIII treatment are enriched in cell cycle and critical beta cell maintenance factors. We also defined the genes that are subject primarily to post-transcriptional control in response to arsenicals and demonstrated that miR-29a is the top candidate master regulator of these genes. Our results highlight the importance of microRNAs in arsenical-induced beta cell dysfunction and reveal both shared and unique mechanisms between iAsIII and MAsIII.

Investigating the Immunomodulatory Potential of Dental Pulp Stem Cell Cultured on Decellularized Bladder Hydrogel towards Macrophage Response In Vitro.

Mesenchymal stem cells (MSCs) possess immunomodulatory properties and capacity for endogenous regeneration. Therefore, MSC therapy is a promising treatment strategy for COVID-19. However, the cells cannot stay in the lung long enough to exert their function. The extracellular matrix from porcine bladders (B-ECM) has been shown not only to regulate cellular activities but also to possess immunoregulatory characteristics. Therefore, it can be hypothesized that B-ECM hydrogel could be an excellent scaffold for MSCs to grow and could anchor MSCs long enough in the lung so that they can exhibit their immunomodulatory functions. In this study, ECM degradation products and a co-culture system of MSCs and macrophages were developed to study the immunomodulatory properties of ECM and MSCs under septic conditions. The results showed that B-ECM degradation products could decrease pro-inflammatory and increase anti-inflammatory cytokines from macrophages. In an in vivo mimicking co-culture system, MSCs cultured on B-ECM hydrogel exhibited immunomodulatory properties at both gene and protein levels. Both B-ECM degradation products and MSC conditioned medium supported the wound healing of alveolar epithelial cells. The results from the study could offer a basis for investigation of immunomodulation by ECM and MSCs before conducting in vivo experiments, which could later be applied in regenerative medicine.

When Does Da Vanci Robotic Surgical Systems Come Into Play?

The emergent of medical science and technology has risen the minimally invasive surgery. Da Vinci Robotic Surgical Systems (RSS) is the trend at present. Compared with the past surgical methods, many studies related to RSS tend to explore postoperative outcomes and quality of life or compare the advantages and disadvantages than the other surgery. Few studies to understand the patients' willing who use RSS. This study mainly explores the patients' willingness and adopts the Technology Acceptance Model (TAM) as the theoretical foundation, and appended the trust concept to discuss. The study was a retrospective study and used a structured questionnaire to conduct a survey. The subjects included the patients with single-disease who had used RSS in a Medical Center of Southern Taiwan but excluded the patients with multiple disorder. This study conducted SPSS 22.0 and Smart PLS 2.0 software for statistical analysis, which included descriptive statistical analysis and applied Partial Least Squares (PLS) analysis to test the research model and to examine the established hypotheses. A total of 136 cases were collected in this study. Study validation was tested. Trust positively affects Perceived Usefulness (ß = 0.550) and Perceived Ease of Use (ß = 0.300). Perceived Ease of Use positively affects Perceived Usefulness (ß = 0.188). Perceived Usefulness positively affects Attitude Toward Using (ß = 0.589. Attitude Toward Using positively affects Behavioral Intention (ß = 0.446. The relationship between perceived Ease of Use and Attitude toward Using was insignificant. Additionally, the relationship between Perceived Usefulness and Behavioral Intention was insignificant. In the research results, we found that patients are mostly in the middle and high age groups, and if the patient himself feels that RSS is extremely helpful to his illness, the intensity of his choice of intention will be high. In comparison, the information related to RSS has been clearly known, it does not directly affect the selection intention. According to age, most of the choices of RSS is based on safety and risk considerations, and it is beneficial to the patient himself, but RSS is also more expensive. We recommended that the government consider ßß reimbursing the RSS process in health insurance programs to meet the needs and expectations of patients.

Multiomic analysis defines the first microRNA atlas across all small intestinal epithelial lineages and reveals novel markers of almost all major cell types.

MicroRNA-mediated regulation is critical for the proper development and function of the small intestinal (SI) epithelium. However, it is not known which microRNAs are expressed in each of the cell types of the SI epithelium. To bridge this important knowledge gap, we performed comprehensive microRNA profiling in all major cell types of the mouse SI epithelium. We used flow cytometry and fluorescence-activated cell sorting with multiple reporter mouse models to isolate intestinal stem cells, enterocytes, goblet cells, Paneth cells, enteroendocrine cells, tuft cells, and secretory progenitors. We then subjected these cell populations to small RNA-sequencing. The resulting atlas revealed highly enriched microRNA markers for almost every major cell type (https://sethupathy-lab.shinyapps.io/SI_miRNA/). Several of these lineage-enriched microRNAs (LEMs) were observed to be embedded in annotated host genes. We used chromatin-run-on sequencing to determine which of these LEMs are likely cotranscribed with their host genes. We then performed single-cell RNA-sequencing to define the cell type specificity of the host genes and embedded LEMs. We observed that the two most enriched microRNAs in secretory progenitors are miR-1224 and miR-672, the latter of which we found is deleted in hominin species. Finally, using several in vivo models, we established that miR-152 is a Paneth cell-specific microRNA.NEW & NOTEWORTHY In this study, first, microRNA atlas (and searchable web server) across all major small intestinal epithelial cell types is presented. We have demonstrated microRNAs that uniquely mark several lineages, including enteroendocrine and tuft. Identification of a key marker of mouse secretory progenitor cells, miR-672, which we show is deleted in humans. We have used several in vivo models to establish miR-152 as a specific marker of Paneth cells, which are highly understudied in terms of microRNAs.

Exploration of Preventable Hospitalizations for Colorectal Cancer with the National Cancer Control Program in Taiwan.

BACKGROUND: Causing more than 40,000 deaths each year, cancer is one of the leading causes of mortality and preventable hospitalizations (PH) in Taiwan. To reduce the incidence and severity of cancer, the National Cancer Control Program (NCCP) includes screening for various types of cancer. A cohort study was conducted to explore the long-term trends in PH/person-years following NCCP intervention from 1997 to 2013. METHODS: Trend analysis was carried out for long-term hospitalization. The Poisson regression model was used to compare PH/person-years before (1997-2004) and after intervention (2005-2013), and to explore the impact of policy intervention. RESULTS: The policy response reduced 26% for the risk of hospitalization; in terms of comorbidity, each additional point increased the risk of hospitalization by 2.15 times. The risk of hospitalization doubled for each 10-year increase but was not statistically significant. Trend analysis validates changes in the number of hospitalizations/person-years in 2005. CONCLUSIONS: PH is adopted as an indicator for monitoring primary care quality, providing governments with a useful reference for which to gauge the adequacy, accessibility, and quality of health care. Differences in PH rates between rural and urban areas can also be used as a reference for achieving equitable distribution of medical resources.

Detecting Effects of Low Levels of FCCP on Stem Cell Micromotion and Wound-Healing Migration by Time-Series Capacitance Measurement.

Electric cell-substrate impedance sensing (ECIS) has been used as a real-time impedance-based method to quantify cell behavior in tissue culture. The method is capable of measuring both the resistance and capacitance of a cell-covered microelectrode at various AC frequencies. In this study, we demonstrate the application of high-frequency capacitance measurement (f = 40 or 64 kHz) for the sensitive detection of both the micromotion and wound-healing migration of human mesenchymal stem cells (hMSCs). Impedance measurements of cell-covered electrodes upon the challenge of various concentrations of carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), from 0.1 to 30 µM, were conducted using ECIS. FCCP is an uncoupler of mitochondrial oxidative phosphorylation (OXPHOS), thereby reducing mitochondrial ATP production. By numerically analyzing the time-series capacitance data, a dose-dependent decrease in hMSC micromotion and wound-healing migration was observed, and the effect was significantly detected at levels as low as 0.1 µM. While most reported works with ECIS use the resistance/impedance time series, our results suggest the potential use of high-frequency capacitance time series for assessing migratory cell behavior such as micromotion and wound-healing migration.

Chromatin regulatory dynamics of early human small intestinal development using a directed differentiation model.

The establishment of the small intestinal (SI) lineage during human embryogenesis ensures functional integrity of the intestine after birth. The chromatin dynamics that drive SI lineage formation and regional patterning in humans are essentially unknown. To fill this knowledge void, we apply a cutting-edge genomic technology to a state-of-the-art human model of early SI development. Specifically, we leverage chromatin run-on sequencing (ChRO-seq) to define the landscape of active promoters, enhancers and gene bodies across distinct stages of directed differentiation of human pluripotent stem cells into SI spheroids with regional specification. Through comprehensive ChRO-seq analysis we identify candidate stage-specific chromatin activity states, novel markers and enhancer hotspots during the directed differentiation. Moreover, we propose a detailed transcriptional network associated with SI lineage formation or regional patterning. Our ChRO-seq analyses uncover a previously undescribed pattern of enhancer activity and transcription at HOX gene loci underlying SI regional patterning. We also validated this unique HOX dynamics by the analysis of single cell RNA-seq data from human fetal SI. Overall, the results lead to a new proposed working model for the regulatory underpinnings of human SI development, thereby adding a novel dimension to the literature that has relied almost exclusively on non-human models.

Lead poisoning due to incense burning: an outbreak in a family.

BACKGROUND: In Asia and some other regions of the world, incense burning is an important folk and cultural activity. However, this ritual can cause health impacts, such as chronic respiratory diseases and neoplasms. Herein, we describe a family with lead poisoning possibly related to the frequent use of incense sticks at home. CASE REPORT: A 65-year-old homemaker with severe anemia, pitting edema of the lower legs, bone pain, abdominal pain, and exertional dyspnea for several months presented to our clinic. Her blood workup indicated severe anemia with basophilic stippling in red blood cells and blood lead level (BLL) of 59.75 µg/dL. Her husband, three children, and four grandchildren who lived with her also had high BLLs. As a Daoist clergy person, she had been exposed to a large amount of smoke from every day use of incense for >30 years. In the field investigation, the chronic dust deposited in hidden corners of their home had considerably higher lead content and other toxic metals. DISCUSSION: Our observations indicated chronic, frequent exposure to smoke from incense burning may be a cause of lead poisoning. Strict avoidance of incense smoke is a significant step toward preventing lead poisoning in children in societies with the custom of incense burning.